JP7055674B2 - Method for Producing Polysilane Composition and Heteroatom-Introduced Polysilane Composition - Google Patents

Description

The present invention relates to a polysilane composition and a method for producing a hetero element-introduced polysilane composition.

Thin-film silicon is used for applications such as solar cells and semiconductors, and this thin-film silicon is conventionally produced by a vapor deposition film forming method (CVD method) using monosilane as a raw material. Other methods for producing the silicon film include a CVD method (Patent Document 1) using a silane hydride compound represented by the general formula (SiH ₂ ) _n (n = 4, 5, or 6) as a raw material, and cyclohexasilane. (Patent Document 2), a method of forming a solution layer containing cyclopentasilane or cyclohexasilane as a solute on a substrate, and producing polysilane by photopolymerization have been reported (Patent Document 3). There is.

As a method for producing a hydride silane compound, a halosilane cyclization reaction is carried out in the presence of a specific coordination compound to obtain a halogenated silane neutral complex, which is then reduced to obtain a hydride silane compound. Is disclosed (Patent Document 4).

On the other hand, when a liquid silane in which a hetero element of Group 13 or 15 is introduced is used as a dopant in manufacturing a solar cell, a semiconductor, etc. at a low temperature and in a large area, the hetero is from the viewpoint of making the distribution of the dopant uniform. Halogen-containing polysilanes that can be replaced with elements are also needed.
As a method for preparing a halogen-containing polysilane substitutable with this hetero element, for example, a method of halogenating a hydrogenated silane with a halogenating reagent and reacting with the hetero element-containing nucleophilic reagent is disclosed (Patent Document 5).

Japanese Unexamined Patent Publication No. 60-26664 Special Table 2013-537705 Gazette Japanese Unexamined Patent Publication No. 2013-187261 Japanese Unexamined Patent Publication No. 2015-134755 Japanese Patent Publication No. 2011-521953

However, in the technique of Patent Document 5, the corresponding hydride silane is halogenated in order to obtain a halogenated silane, and at this time, a metal halide is used as a halogenating reagent for halogenation. The reaction is photosensitive, harmful substances are generated, and many unreacted substances are present, making it difficult to control the reaction. Moreover, metal halides are added in excess as a solid. There is a problem that metal impurities derived from metal halides are contained, and as a result, purification of the product becomes difficult.
On the other hand, the metal impurities include, for example, an aluminum-containing substance derived from a reaction raw material, a free substance of halosilane, and an aluminum-containing substance derived from a hydrogenated silane compound obtained by using a reducing agent, and the aluminum content is high. In that case, the hydrogenated silane compound may be polymerized, which tends to cause a problem in terms of long-term storage stability of the hydrogenated silane.
Therefore, the present invention provides a polysilane composition in which the amount of metal impurities such as aluminum content is reduced and a hetero element can be introduced without using a metal halide for halogenating the hydrogenated silane, and a hetero element. The subject was to provide a method for producing a polysilane composition that can be introduced.

The gist of the present invention is as follows.

[1] Halosilane represented by the general formula Silicon X _{2 m} (m = 3 to 8, X is a halogen element) and hydrogenated silane represented by the general formula Silicon H _2n ( _n = 3 to 8). A polysilane composition comprising, characterized in that the aluminum content is 0.01 ppb to 1000 ppm on a mass basis.
[2] The polysilane composition according to [1], wherein the hydrogenated silane is a reaction product of a halosilane for preparing hydrogenated silane and a reducing agent, and the halosilane is an externally added halosilane.
[3] The polysilane composition according to [1] or [2], wherein the purity of the hydrogenated silane is 90% by mass or more.
[4] The polysilane composition according to any one of [1] to [3], wherein the content (based on mass) of the halosilane is 0.01 to 10 mol with respect to 1 mol of the hydrogenated silane.
[5] The polysilane composition according to any one of [1] to [4], wherein at least a part of the halogen element contained in the halosilane is replaced with at least one element selected from Group 13 and Group 15. ..
[6] The polysilane composition according to any one of [1] to [5], wherein the halosilane is a cyclic halosilane represented by the general formula Silicon X _{2 m} (m = 5 to 6, X is a halogen element).
[7] The polysilane composition according to [6], wherein the cyclic halosilane is cyclic chlorosilane.
[8] The polysilane composition according to [7], wherein the cyclic chlorosilane is dodecachlorocyclohexasilane.
[9] The polysilane composition according to any one of [1] to [8], wherein the hydrogenated silane is a cyclic hydride (n = 5 to 6) represented by the general formula Si _n H _2n .
[10] The polysilane composition according to [9], wherein the cyclic hydrogenated silane is cyclohexasilane.
[11] A method for producing a polysilane composition into which a hetero element has been introduced.
A halosilane represented by the general formula Silicon X _{2 m} (m = 3 to 8, X is a halogen element) and a hydrogenated silane represented by the general formula Silicon H _2n ( _n = 3 to 8) are mixed and / /. Alternatively, a production method comprising a step of contacting, wherein the aluminum content is 0.01 ppb to 1000 ppm on a mass basis.
[12] The production method according to [11], wherein the mixture of the halosilane and the hydrogenated silane is a solution.
[13] The production method according to [11] or [12], further comprising a step of mixing and / or contacting a compound having at least one element selected from Group 13 and Group 15.

According to the present invention, a polysilane composition in which the amount of metal impurities such as aluminum content can be reduced and a hetero element can be introduced without using a metal halide for halogenating silane hydride, and a hetero element can be obtained. It becomes possible to provide a method for producing a polysilane composition that can be introduced. Further, it is possible to provide a polysilane composition (for doping) containing various functional groups in an arbitrary ratio.

1. 1. Polysilane composition The polysilane composition of the present invention comprises halosilane (m = 3 to 8, X is a halogen element) represented by the general formula Silicon X _2m and hydrogenated silane represented by the general formula _{Silicon H 2n ( m} = 3 to 8, X is a halogen element). It is characterized by containing n = 3 to 8) and having an aluminum content of 0.01 ppb to 1000 ppm on a mass basis.
The polysilane composition of the present invention can contain a hetero element in an arbitrary ratio by adjusting the number of halogen elements contained in the halosilane and the amount of the halosilane relative to the amount of the hydrogenated silane, and halogenate the hydrogenated silane. Since the reaction can proceed in a liquid without using a metal halide for the purpose, it is possible to reduce the amount of metal impurities.

The halosilane is a cyclic halosilane represented by the general formula Silicon X _2m ( _m = 3 to 8, X is a halogen element).
The halogen element is preferably a chlorine element, a fluorine element, a bromine element, or an iodine element. m is preferably 4 to 7, and more preferably 5 to 6.

The halosilane is a cyclic halosilane, that is, a compound having a structure in which silicon atoms are connected to form a monoprime ring and a halogen atom is bonded to at least one silicon atom constituting the monoprime ring (cyclic halosilane structure). It is preferable to have.

The cyclic halosilane may contain a silicon atom that does not form a monoprime ring, and for example, even if a substituent containing a silicon atom (for example, a silyl group) is bonded to the silicon atom that constitutes the monoprime ring. good. At least one halogen atom may be bonded to the monoelement ring formed from the silicon atom, and preferably one or two halogen atoms are bonded to each of the silicon atoms constituting the monoelement ring (preferably). 2) They are combined.

Among them, the cyclic halosilane is more preferably cyclicchlorosilane, further preferably cyclicchlorosilane having 5 or 6 silicon numbers, and further preferably dodecachlorocyclohexasilane.

The content of halosilane (based on mass) is preferably 0.01 to 10 mol, more preferably 0.05 to 9 mol, still more preferably 0.1 to 7 mol, and even more, relative to 1 mol of hydrogenated silane. It is preferably 0.2 to 5 mol.

The hydrogenated silane is a cyclic hydride represented by the general formula Si _n H _2n (n = 3 to 8).
The halogen element is preferably a chlorine element, a fluorine element, a bromine element, or an iodine element. n is preferably 4 to 7, and more preferably 5 to 6.

The hydride is preferably a cyclic hydride, that is, a compound having a monoprime ring composed of a series of silicon atoms and composed of a silicon atom and a hydrogen atom. In the cyclic hydride silane, a hydrogen atom may be bonded to all the substitution positions of the silicon atom constituting the monoelement ring, and an unsubstituted silyl group is bonded to the silicon atom constituting the monoelement ring. There may be. However, from the viewpoint of storage stability, it is preferable that the silicon atom other than the silicon atom constituting the monoprime ring is not contained.

Among them, the cyclic hydrogenated silane is more preferably a cyclic hydrogenated silane having 5 or 6 silicon atoms, and further preferably cyclohexasilane.

The purity of the hydrogenated silane may be based on, for example, gas chromatography, and is preferably 90% by mass or more, more preferably 93% by mass or more, and further preferably 95% by mass or more. It is more preferably 97% by mass or more, and particularly preferably 98% by mass or more. The upper limit of the purity of silane hydride is better as it is closer to 100% by mass, for example, 99.99% by mass.

Such purity can be determined using, for example, the following gas chromatography conditions.
Detection: FID
Column: Capillary column with poly (5% diphenyl / 95% dimethyl) siloxane phase, 0.25 μm x 0.25 mm x 30 m
Vaporization chamber temperature: 250 ° C
Detector temperature: 280 ° C
Temperature rise conditions: 1) Hold at 50 ° C for 5 minutes, 2) Heat up to 250 ° C at a temperature rise rate of 20 ° C / min, 3) Raise to 280 ° C at a temperature rise rate of 10 ° C / min, 4) 10 at 280 ° C. Hold minutes

The hydrogenated silane of the present invention may be, for example, prepared cyclohexasilane of cyclic hydrogenated silane, solid-liquid separated cyclohexasilane, or distilled cyclohexasilane. May be.

The hydrogenated silane of the present invention may be, for example, cyclized of a halogenated monosilane, preparation of a cyclic halosilane salt, liberation of a cyclic halosilane salt, reduction of a cyclic halosilane compound, and the hydrogenated silane is produced by a reducing agent. It is preferably obtained.

As the reducing agent, it is preferable to use one or more selected from the group consisting of an aluminum-based reducing agent and a boron-based reducing agent. Examples of the aluminum-based reducing agent include lithium aluminum hydride (LiAlH ₄ ; LAH), diisobutylaluminum hydride (DIBAL), and bis (2-methoxyethoxy) aluminum sodium hydride [“Red-Al” (Sigma Aldrich). Metal hydrides such as [registered trademark)] and the like can be mentioned. Examples of the boron-based reducing agent include metal hydrides such as sodium borohydride and lithium triethylborohydride, diborane and the like, and it is preferable to use metal hydrides.

The aluminum content in the polysilane composition is 0.01 ppb to 1000 ppm on a mass basis, preferably 100 ppm or less, more preferably 1000 ppb or less, still more preferably 500 ppb or less.
When silane hydride is obtained through a reduction step, it contains several thousand ppm to several percent of a metal element derived from a reducing agent. Further, when a mixture of hydrogenated silane and unreacted halosilane is obtained in the reduction step, it is difficult to purify the mixture while maintaining the mixed state, so that it is difficult to obtain the above aluminum content.

The aluminum content can be determined by, for example, ICP mass spectrometry, ICP emission spectrometry, atomic absorption spectrometry, etc., and Agilent 7700S (manufactured by Agilent Technologies) may be used.

The polysilane composition does not have to contain a solvent, and may contain a solvent.
The solvent may be any solvent that does not react with halosilane or hydride silane, and is an aliphatic hydrocarbon solvent such as hexane, heptane or octane; an aromatic hydrocarbon solvent such as benzene, toluene or xylene; diethyl ether, tetrahydrofuran or cyclopentylmethyl. It may be an ether solvent such as ether.

The amount of the solvent is preferably 1 to 10000 parts by mass, more preferably 10 to 8000 parts by mass, and further preferably 100 to 6000 parts by mass with respect to 100 parts by mass of the total of halosilane and hydrogenated silane.

The polysilane composition containing silane hydride and halosilane may continue to be doped, if necessary.
In the present invention, it is preferable that at least a part of the halogen element contained in halosilane is substituted with at least one element selected from Group 13 and Group 15 (also referred to as a hetero element) and a substituent containing the element. It is more preferable that all of the halogen elements contained in Halosilane are substituted with at least one element selected from Groups 13 and 15 and a substituent containing the elements.

Examples of the Group 13 element include B, Al, Ga, In, Tl and the like, and examples of the Group 15 element include N, P, As, Sb, Bi and the like.

These elements can be introduced into halosilane by using a nucleophile.
Examples of the nucleating reagent include BR ₃ , B ₂ H ₆ , NR ₃ , PR ₃ , AsR ₃ (R = H, or an alkyl group having 1 to 6 carbon atoms), and an alkali metal salt XMR ₃ (X = Na, Li). Alkali metals such as, M = Group 13 or Group 15 elements, R = H, or alkyl groups having 1 to 6 carbon atoms) and the like.

The element selected from Group 13 and Group 15 as a heteroatom is replaced with a halogen element bonded to halosilane. By appropriately adjusting the number of halogen elements contained in halosilane and the amount of halosilane with respect to hydrogenated silane, a polysilane composition in which a predetermined amount of various heteroelements are introduced can be prepared.

In the polysilane composition into which the hetero element was introduced, the ratio of the hydrogenated silane to the silane in which the halogen element was replaced with the hetero element was the same as the ratio of the hydrogenated silane to the halosilane before the hetero element was introduced. May be.

2. 2. Method for producing a polysilane composition into which a hetero element can be introduced The method for producing a polysilane composition into which a hetero element of the present invention has been introduced is a halosilane represented by the general formula Silicon X _{2 m} (m = 3 to 8, X is a halogen element). ) And silane hydride ( _n = 3-8) represented by the general formula Sin H _2n are mixed and / or brought into contact with each other, and the aluminum content is 0.01 ppb to 1000 ppm on a mass basis. It is characterized by that.

The method for producing halosilane is not particularly limited, and various known production methods can be adopted, and a method for liberating a cyclic halosilane salt prepared by cyclization of a halogenated monosilane is preferable.
The method for producing hydrogenated silane is not particularly limited, and various known production methods can be adopted, and a method for reducing liberated cyclic halosilane is preferable.

<Halogenated monosilane cyclization reaction>
Examples of the halogenated monosilane include dihalosilanes such as dichlorosilane, dibromosilane, diiodosilane, and difluorosilane; trihalosilanes such as trichlorosilane, tribromosilane, triiodosilane, and trifluorosilane; tetrachlorosilane, tetrabromosilane, and tetra. Tetrahalosilanes such as iodosilane and tetrafluorosilane; and the like can be used. Among these, trihalosilane is preferable, and trichlorosilane is particularly preferable.

The method for cyclizing the halogenated monosilane is not particularly limited, but for example, the method (A) or (B) below is preferable.
(A) A method for obtaining a salt of cyclic halosilane, which comprises a step of contacting a halogenated monosilane with a phosphonium salt and / or an ammonium salt [hereinafter, may be referred to as method A].
(B) A method for obtaining a cyclic halosilane neutral complex, which comprises a step of contacting a halogenated monosilane with at least one compound selected from the group consisting of the following (I) and (II) [hereinafter referred to as Method B]. May].

(I) A compound represented as XR _n [hereinafter, may be referred to as compound I]. When X is P or P = O, n = 3, and R represents the same or different substituted or unsubstituted alkyl or aryl group. When X is S, S = O, O, n = 2, and R represents the same or different substituted or unsubstituted alkyl or aryl group. When X is CN, n = 1, and R represents a substituted or unsubstituted alkyl group or aryl group. However, the number of amino groups in XR _n is 0 or 1.

(II) At least one heterocyclic compound selected from the group consisting of substituted or unsubstituted heterocyclic compounds containing N, O, S or P having an unshared electron pair in the ring [hereinafter referred to as compound II]. There is]. However, the number of tertiary amino groups as substituents of the heterocyclic compound is 0 or 1.

First, the above method (A) will be described.

The phosphonium salt is preferably a quaternary phosphonium salt, and a salt represented by the following formula (11) is preferably mentioned. In the following formula (11), R ¹ to R ⁴ may be different from each other, but it is preferable that they are all the same group.

Further, the ammonium salt is preferably a quaternary ammonium salt, and a salt represented by the following formula (12) is preferably mentioned. In the following formula (12), R ⁵ to R ⁸ may be different from each other, but it is preferable that they are all the same group.

In the above formula (11) and the above formula (12), R ¹ to R ⁴ and R ⁵ to R ⁸ independently represent a hydrogen atom, an alkyl group, and an aryl group, ^and A- represents a monovalent anion. ..

The alkyl groups of R ¹ to R ⁴ and R ⁵ to R ⁸ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group and an undecyl group. Linear alkyl groups such as group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group and hexadecyl group; cyclic alkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group and cyclohexyl group can be mentioned. ..
The number of carbon atoms of the alkyl group is preferably 1 to 16, and more preferably 1 to 8.

As the aryl group of R ¹ to R ⁴ and R ⁵ to R ⁸ , an aryl group having 6 to 18 carbon atoms such as a phenyl group and a naphthyl group is preferable, and an aryl group having 6 to 12 carbon atoms is more preferable.

The R ¹ to R ⁴ and R ⁵ to R ⁸ are preferably an alkyl group or an aryl group, more preferably an aryl group. When R ¹ to R ⁴ and R ⁵ to R ⁸ are aryl groups, as described later, when the salt of the cyclic halosilane is produced, the salt of the cyclic halosilane is precipitated and formed in the reaction solution to form the cyclic halosilane. It becomes easy to obtain the salt with high purity. Also, for the same reason, it is preferable to use a phosphonium salt rather than an ammonium salt.

In the above formulas (11) and (12), the monovalent anion represented by A- includes halide ions (for example, ^{Cl- ,} Br- ^, I- ^, etc.) and borate ions (for example, BF _4- ⁾ . , Phosphorus anions (eg, PF _6- ⁾ and the like. Among these, halide ions are preferable from the viewpoint of easy availability, more preferably ^Cl- , Br-, I- ^{, and} particularly preferably ^{Cl- ,} Br-.

Either one of the phosphonium salt and the ammonium salt may be used, or both may be used. As the phosphonium salt, only one kind may be used, or two or more kinds may be used in combination. Only one type of ammonium salt may be used, or two or more types may be used in combination.

The amount of the phosphonium salt and / or ammonium salt used (the total amount used when two or more kinds are used) is preferably 0.01 mol or more, more preferably 0.05 mol or more, still more preferably 0.05 mol or more with respect to 1 mol of halosilane. It is 0.08 mol or more, preferably 1.0 mol or less, more preferably 0.7 mol or less, still more preferably 0.5 mol or less. When the amount of the phosphonium salt and / or the ammonium salt used is in the above range, the yield of the cyclic halosilane salt tends to be improved.

The above method (A) is preferably performed in the presence of a chelated ligand such as a polyether, a polythioether, or a polydentate phosphine. By carrying out the cyclization coupling reaction in the presence of a chelate-type ligand, a salt of cyclic halosilane can be efficiently produced. Further, the number of hydrogens and the composition ratio in the obtained cyclic halosilane can be adjusted by appropriately selecting the type of chelate-type ligand to be used.

Examples of the polyether include 1,1-dimethoxyethane, 1,2-dimethoxyethane, 1,2-diethoxyethane, 1,2-dipropoxyetane, 1,2-diisopropoxyetane, 1,2. -Dibutoxyethane, 1,3-dimethoxypropane, 1,3-diethoxypropane, 1,3-dipropoxypropane, 1,3-diisopropoxypropane, 1,3-dibutoxypropane, 1,4-dimethoxy Dialkoxy alkanes such as butane, 1,4-diethoxybutane, 1,4-dipropoxybutane, 1,4-diisopropoxybutane, 1,4-dibutoxybutane, 1,2-diphenoxyethane, 1, , 3-Diphenoxypropane, 1,4-diphenyloxyalkanes such as diphenoxybutane and the like. Among these, 1,2-dimethoxyethane is particularly preferable.

Examples of the polythioether include those in which the oxygen atom of the above-exemplified polyether is replaced with a sulfur atom.

Examples of the polydentate phosphin include 1,2-bis (dimethylphosphino) ethane, 1,2-bis (diethylphosphino) ethane, 1,2-bis (dipropylphosphino) ethane, 1,2-. Bis (dibutylphosphino) ethane, 1,3-bis (dimethylphosphino) propane, 1,3-bis (diethylphosphino) propane, 1,3-bis (dipropylphosphino) propane, 1,3-bis (Dibutylphosphino) propane, 1,4-bis (dimethylphosphino) butane, 1,4-bis (diethylphosphino) butane, 1,4-bis (dipropylphosphino) butane, 1,4-bis ( Dibutylphosphino) Butane and other bis (dialkylphosphino) alkanes; 1,2-bis (diphenylphosphino) ethane, 1,3-bis (diphenylphosphino) propane, 1,4-bis (diphenylphosphino) Examples thereof include bis (diarylphosphino) alkanes such as butane. Among these, 1,2-bis (diphenylphosphino) ethane is particularly preferable.

The amount of the chelate-type ligand used may be appropriately set, and for example, it is preferably 0.01 mol or more, more preferably 0.05 mol or more, still more preferably 0.1 mol or more, and more preferably 0.1 mol or more with respect to 1 mol of halosilane. Is 50 mol or less, more preferably 40 mol or less, still more preferably 30 mol or less.

The salt of the cyclic halosilane obtained by the above method (A) is preferably represented by the following formula (13), for example.

In the above formula (13), X ¹ and X ² each independently represent a halogen atom, L represents an anionic ligand, and p represents an integer of -2 to 0 as the valence of the ligand L. , K represents a counter cation, q represents an integer of 0 to 2 as the valence of the counter cation K, n represents an integer of 0 to 5, a, b and c are integers of 0 or more and “2n + 6” or less. (However, a + b + c = 2n + 6, and a and c are not 0 at the same time), d is an integer of 0 to 3 (however, a and d are not 0 at the same time), and e is an integer of 0 to 3 (provided that it is not 0 at the same time). , D + e = 3), m is 1 to 2, s represents an integer of 1 or more, and t represents an integer of 1 or more.

<Method of releasing cyclic halosilane salt>
The salt of the cyclic halosilane may be made into a free cyclic halosilane by contacting it with Lewis acid and reacting it. The free cyclic halosilane means, for example, a non-complex type cyclic halosilane such as Si ₅ Cl ₁₀ or Si ₆ Cl ₁₂ . Specifically, when a salt of cyclic halosilane is brought into contact with Lewis acid, Lewis acid acts electrophilically on the anionic ligand contained in the salt of cyclic halosilane, and anionic coordination is performed from the salt of cyclic halosilane. As the offspring are withdrawn, the counter cation is liberated to give the corresponding free cyclic halosilane.

The type of Lewis acid is not particularly limited, but it is preferable to use a metal halide. Examples of the metal halide include metal chloride, metal bromide, and metal iodide, but it is preferable to use metal chloride from the viewpoint of reactivity and ease of control of the reaction. The metal elements constituting the metal halide include Group 13 elements such as boron, aluminum, gallium, indium and tarium, Group 11 elements such as copper, silver and gold, Group 4 elements such as titanium and zirconium, iron and zinc. Examples include calcium. Specific examples of the Lewis acid include boron halides such as boron trifluoride, boron trichloride and boron tribromide; aluminum halides such as aluminum chloride and aluminum bromide; halogenation of gallium chloride and gallium bromide. Gallium; Indium halide such as indium chloride and indium bromide; Talium halide such as tallium chloride and talium bromide; Copper halide such as copper chloride and copper bromide; Silver halide such as silver chloride and silver bromide; Halogenated gold such as gold chloride and gold bromide; Titanium halide such as titanium chloride and titanium bromide; Halogenated zirconium such as zirconium chloride and zirconium bromide; Iron halide such as iron chloride and iron bromide; Zinc chloride , Halogenated zinc such as zinc bromide; calcium halide, calcium halide such as calcium bromide; and the like.

The amount of the Lewis acid used may be appropriately adjusted according to the reactivity between the salt of the cyclic halosilane and the Lewis acid, and is preferably 0.5 mol or more, more preferably 0.5 mol or more, with respect to 1 mol of the salt of the cyclic halosilane, for example. It is 1.5 mol or more, preferably 20 mol or less, and more preferably 10 mol or less.

The reaction between the cyclic halosilane salt and Lewis acid is preferably carried out in a solvent or a dispersion medium (these are simply referred to as a solvent). Examples of the solvent (reaction solvent) used in the reaction include hydrocarbon solvents such as hexane and toluene; ether solvents such as diethyl ether, tetrahydrofuran, cyclopentyl methyl ether, diisopropyl ether and methyl tertiary butyl ether. Only one kind of these organic solvents may be used, or two or more kinds thereof may be used in combination. The reaction solvent is preferably purified by distillation, dehydration or the like before the reaction in order to remove water and dissolved oxygen contained therein.

The reaction temperature at the time of reacting the above cyclic halosilane salt with Lewis acid may be appropriately adjusted according to the reactivity, but for example, it is preferably −80 ° C. or higher, more preferably −50 ° C. or higher, still more preferable. Is −30 ° C. or higher, preferably 200 ° C. or lower, more preferably 150 ° C. or lower, still more preferably 100 ° C. or lower.

Next, the above method (B) will be described.

In XR _n of the above compound I, X coordinates with the cyclic halosilane to form a cyclic halosilane neutral complex. When X is P or P = O, X is trivalent and n, which indicates the number of R, is 3. R represents the same or different substituted or unsubstituted alkyl or aryl group. More preferably, R is a substituted or unsubstituted aryl group. When R is an alkyl group, a linear, branched or cyclic alkyl group can be mentioned, including a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group and a nonyl group. , Decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group and other linear alkyl groups; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group and other cyclic groups. An alkyl group having 1 to 16 carbon atoms such as an alkyl group is preferably used. When R is an aryl group, an aryl group having about 6 to 18 carbon atoms such as a phenyl group and a naphthyl group is preferably mentioned.

In XR _n of the above compound I, even when X is N, X coordinates with the cyclic halosilane to form a cyclic halosilane neutral complex. However, the number of amino groups in XR _n is 1. When X is N, X is trivalent and n, which indicates the number of R, is 3. R represents the same or different substituted or unsubstituted alkyl or aryl group. R is more preferably a substituted or unsubstituted alkyl group. When R is an alkyl group, a linear, branched or cyclic alkyl group is mentioned, and an alkyl group having 1 to 16 carbon atoms is preferable, and an alkyl group having 1 to 16 carbon atoms such as a methyl group, an ethyl group, a propyl group and a butyl group is preferable. Alkyl groups of to 4 are more preferable, and alkyl groups having 1 to 3 carbon atoms are further preferable. When R is an aryl group, an aryl group having about 6 to 18 carbon atoms such as a phenyl group and a naphthyl group is preferably mentioned.

In XR _n when X is P and P = O or when X is N, the substituents that the alkyl group may have include an alkoxy group, an amino group, a cyano group, a carbonyl group and a sulfonyl group. Examples of the substituent which the aryl group may have include an alkoxy group, an amino group, a cyano group, a carbonyl group, a sulfonyl group and the like. Examples of the amino group include a dimethylamino group and a diethylamino group, but the number of amino groups is one or less in XR ₃ , and the purpose is to exclude tertiary polyamines. The three Rs may be the same or different.

When the above X is S, S = O, O, X is divalent and n indicating the number of R is 2. R has the same meaning as R when X is P, P = O, and is a substituted or unsubstituted alkyl group or aryl group. More preferably, R is a substituted or unsubstituted aryl group. Further, when X is CN, X is monovalent and n indicating the number of R is 1. Again, R has the same meaning as R when X is P, P = O, and is a substituted or unsubstituted alkyl or aryl group. More preferably, R is a substituted or unsubstituted aryl group.

As specific examples of the above-mentioned compound I, X such as triphenylphosphine (PPh ₃ ), triphenylphosphine oxide (Ph ₃ P = O), tris (4-methoxyphenyl) phosphine (P (MeOPh) ₃ ) is P or Examples thereof include compounds having P = O; compounds having X of S = O such as dimethyl sulfoxide; compounds having X of CN such as p-tolunitrile (also referred to as p-methylbenzonitrile).

The heterocyclic compound (Compound II) of (II) above needs to have an unshared electron pair in the ring, and the unshared electron pair is coordinated to the cyclic halosilane to be neutral to the cyclic halosilane. Form a complex. Examples of such a heterocyclic compound include one or more substituted or unsubstituted heterocyclic compounds containing N, O, S or P having a lone pair in the ring. The substituent which the heterocyclic compound may have is the same as the substituent which may have when R is an aryl group. Examples of the heterocyclic compound include pyridines, imidazoles, pyrazoles, oxazoles, thiazoles, imidazolines, pyrazines, thiophenes, furans and the like. Specific examples include N, N-dimethyl-4-aminopyridine, tetrahydrothiophene, tetrahydrofuran and the like.

Of the above-mentioned compound I and the above-mentioned compound II, the compound which is liquid at the reaction temperature can also serve as a solvent.

The amounts of the above-mentioned compound I and the above-mentioned compound II to be used may be appropriately determined, and the above-mentioned compound may be used, for example, 0.1 to 50 mol, preferably 0.5 to 3 mol, with respect to 6 mol of halosilane.

The cyclic halosilane neutral complex obtained by the method (B) is formed from 3 to 8 (preferably 5 or 6, particularly 6) silicon atoms of the halosilane as a raw material, and the silicon atoms are linked. It is a complex containing a ring and can be represented by the general formula [Y] _l [Si _m Z _{2m-a Ha} ]. In the above general formula, Y is the above compound I or the above compound II, Z represents the same or different halogen atom of any of Cl, Br, I and F, l is 1 or 2, and m is 3. -8, preferably 5 or 6, particularly preferably 6, a is 0 to 2 m-1, preferably 0 to m.

The cyclization reaction of halosilane in the above method (A) and the above method (B) is preferably carried out by adding a tertiary amine. Hydrochloric acid produced by adding a tertiary amine can be neutralized.

Examples of the tertiary amine used in the cyclization reaction include triethylamine, tripropylamine, tributylamine, trioctylamine, triisobutylamine, triisopentylamine, diethylmethylamine, diisopropylethylamine (DIPEA), and dimethylbutylamine. , Dimethyl-2-ethylhexylamine, diisopropyl-2-ethylhexylamine, methyldioctylamine and the like are preferably mentioned.

As the tertiary amine, one kind may be used, or two or more kinds may be used in combination. In addition, tertiary amines include those that coordinate to cyclic halosilanes. For example, amines that are not relatively bulky and have high symmetry, such as diethylmethylamine and triethylamine, are coordinated relatively efficiently. It is thought that. However, since the yield of the cyclic halosilane neutral complex tends to be low only with the tertiary amine represented by XR _n of the compound I, it is preferable to use the compound I other than the tertiary amine in combination.

The tertiary amine is preferably 0.5 to 4 mol with respect to 1 mol of halosilane, and particularly preferably 1 mol.

In the present invention, although not limited, it is preferable not to use a tertiary polyamine having two or more carbon atoms and three or more amino groups. When the above tertiary polyamine is used, a salt of cyclic halosilane containing silicon as a counter cation is generated, and silane gas is generated during storage or reduction reaction, which is not preferable from the viewpoint of safety.

The cyclization reaction of the halosilane in the method (A) and the method (B) can be carried out in an organic solvent, if necessary. As the organic solvent, a solvent that does not interfere with the cyclization reaction is preferable, and for example, a hydrocarbon solvent (for example, hexane, heptane, benzene, toluene, etc.) and a halogenated hydrocarbon solvent (for example, chloroform, dichloromethane, 1, 2-Dichloroethane, etc.), ether solvents (eg, diethyl ether, tetrahydrofuran, cyclopentylmethyl ether, diisopropyl ether, methyl tertiary butyl ether, etc.), acetonitrile and other aprotonic polar solvents are preferable. Among these, chlorinated hydrocarbon solvents such as chloroform, dichloromethane and 1,2-dichloroethane are preferable, and 1,2-dichloroethane is particularly preferable. In addition, these organic solvents may use 1 type or may use 2 or more types in combination.

The amount of the organic solvent used is not particularly limited, but it is usually preferable to adjust the concentration of halosilane to be 0.5 to 10 mol / L, more preferably 0.8 to 8 mol / L, still more preferable. The concentration is 1 to 5 mol / L.

The reaction temperature in the cyclization reaction can be appropriately set according to the reactivity, and is, for example, about 0 to 120 ° C., preferably about 15 to 70 ° C. It is also recommended that the cyclization reaction be carried out in an atmosphere of an inert gas such as nitrogen.

After the cyclization reaction, it is preferable to include a step of washing the reaction solution containing the cyclic halosilane with a non-halogen solvent. That is, when the cyclization reaction is completed, a solution or dispersion of cyclic halosilane (salt of cyclic halosilane, free cyclic halosilane, cyclic halosilane neutral complex, etc.) is produced. This is concentrated or filtered, and the obtained solid is obtained from a halogen solvent such as chloroform, dichloromethane or 1,2-dichloroethane, an aprotic polar solvent such as acetonitrile, or a hydrocarbon solvent such as hexane, heptane, benzene or toluene. It may be purified by washing with a non-halogen solvent or the like.

Prior to cleaning with the non-halogen solvent, it is preferable to include a step of cleaning with a halogen solvent. The amine hydrochloride can be removed by washing with a halogen solvent, and the halogen solvent can be removed by washing with a non-halogen solvent.

The cleaning using the halogen solvent and the cleaning using the non-halogen solvent may be performed once or twice or more.
By these washing, filtration steps, crystallization, adsorption, etc., the aluminum content in the cyclic halosilane will be sufficiently reduced.

The cyclic halosilane can be obtained as a high-purity solid by purification. However, if desired, it can also be obtained as a composition containing a cyclic halosilane containing impurities. The composition containing the cyclic halosilane preferably contains 80% by mass or more of the cyclic halosilane, more preferably 90% by mass or more, still more preferably 95% by mass or more. The upper limit is, for example, 99.99% by mass. Examples of the impurities include a solvent, the residue of the compound I or the compound II, a decomposition product of cyclic halosilane, a halosilane polymer, and the like. The content of the impurities in the composition containing cyclic halosilane is preferably 20% by mass or less, more preferably 10% by mass or less, further preferably 5% by mass or less, and the lower limit is, for example, 0.01% by mass. %.
The cyclic halosilane thus obtained is preferably used as the halosilane of the present invention.

<Method for reducing cyclic halosilane (method for preparing cyclic hydride)>
By including the step of reducing the cyclic halosilane (salt of cyclic halosilane, free cyclic halosilane, cyclic halosilane neutral complex, etc.) (reduction step), hydrogenated silane containing cyclic hydride can be produced. The reduction step is preferably carried out in the presence of a reducing agent.

The reducing agent that can be used in the reduction step is not particularly limited, but it is preferable to use one or more selected from the group consisting of an aluminum-based reducing agent and a boron-based reducing agent. Examples of the aluminum-based reducing agent include lithium aluminum hydride (LiAlH ₄ ; LAH), diisobutylaluminum hydride (DIBAL), and bis (2-methoxyethoxy) aluminum sodium hydride [“Red-Al” (Sigma Aldrich). Metal hydrides such as [registered trademark)] and the like can be mentioned. Examples of the boron-based reducing agent include metal hydrides such as sodium borohydride and lithium triethylborohydride, diborane and the like, and it is preferable to use metal hydrides. One type of reducing agent may be used, or two or more types may be used in combination.

The amount of the reducing agent used in the reducing step may be appropriately set, and for example, the equivalent of hydride in the reducing agent to one silicon-halogen bond of cyclic halosilane is preferably at least 0.9 equivalent or more. The amount of the reducing agent used is more preferably 1.0 to 50 equivalents, still more preferably 1.0 to 30 equivalents, particularly preferably 1.0 to 15 equivalents, and most preferably 1.0 to 2 equivalents. If the amount of the reducing agent used is too large, the post-treatment takes time and the productivity tends to decrease. On the other hand, if the amount of the reducing agent used is too small, the halogen remains unreduced and the yield tends to decrease.

The molar ratio of cyclic halosilane / reducing agent is preferably 1: 3-4, more preferably 1: 3. If it exceeds this range, the reduction reaction may proceed excessively and the amount of normal hexasilane which is a ring-opening product may be increased.

In the reduction step, a Lewis acid catalyst may be used in combination with the reducing agent as a reducing aid. As the Lewis acid catalyst, chlorides such as aluminum chloride, titanium chloride, zinc chloride, tin chloride and iron chloride; bromides such as aluminum bromide, titanium bromide, zinc bromide, tin bromide and iron bromide; iodide Iodides such as aluminum, titanium iodide, zinc iodide, tin iodide, iron iodide; fluorides such as aluminum fluoride, titanium fluoride, zinc fluoride, tin fluoride, iron fluoride; Metal compounds can be mentioned. These may be used alone or in combination of two or more.

The reaction in the reduction step can be carried out in the presence of an organic solvent, if necessary. Examples of the organic solvent include hydrocarbon solvents such as hexane and toluene; ether solvents such as diethyl ether, tetrahydrofuran, cyclopentyl methyl ether, diisopropyl ether and methyl tertiary butyl ether; and the like. One type of these organic solvents may be used, or two or more types may be used in combination. Further, the organic solvent solution obtained when producing the cyclic halosilane may be used as it is as the organic solvent solution in the reduction step, or the organic solvent is distilled off from the organic solvent solution containing the cyclic halosilane to obtain a new solution. The reduction step may be carried out by adding an organic solvent. The organic solvent used in the reaction in the reduction step is preferably purified by distillation, dehydration or the like before the reaction in order to remove water and dissolved oxygen contained therein.

The amount of the organic solvent used in the reduction reaction is preferably adjusted so that the concentration of the cyclic halosilane is 0.01 to 1 mol / L, more preferably 0.02 to 0.7 mol / L, and even more preferably 0.02 to 0.7 mol / L. It is 0.03 to 0.5 mol / L. By carrying out the reaction in the above range, the content of impurities such as halogen elements contained in the hydrogenated silane composition tends to be remarkably reduced.

The reduction can be carried out by contacting the cyclic halosilane with the reducing agent. When the cyclic halosilane is brought into contact with the reducing agent, it is preferable to bring them into contact with each other in the presence of a solvent. To bring the cyclic halosilane into contact with the reducing agent in the presence of a solvent, for example, (a) the reducing agent is added as it is to the solution or dispersion of the cyclic halosilane, and (b) the cyclic halosilane is reduced to the solution or dispersion. A mixing procedure such as adding a solution or dispersion in which the agent is dissolved or dispersed in a solvent, or (c) adding the cyclic halosilane and the reducing agent to the solvent simultaneously or sequentially may be adopted. Of these, the aspect (b) above is particularly preferable.

Further, when the cyclic halosilane is brought into contact with the reducing agent, it is preferable to drop at least one of the cyclic halosilane solution or dispersion and the reducing agent solution or dispersion into the reaction system for reduction. By dropping one or both of the cyclic halosilane and the reducing agent in this way, the heat generated by the reduction reaction can be controlled by the dropping speed, etc. The effect that leads to improvement can be obtained.

The following three embodiments are preferable in the case of dropping one or both of the cyclic halosilane and the reducing agent. That is, A1) a mode in which a solution or dispersion of cyclic halosilane is charged in a reactor and a solution or dispersion of a reducing agent is dropped onto the solution, B1) a solution or dispersion of a reducing agent is charged in the reactor. A mode in which a solution or dispersion of cyclic halosilane is dropped onto the solution, and a mode in which the solution or dispersion of cyclic halosilane and a solution or dispersion of a reducing agent are simultaneously or sequentially dropped into the reactor. Among these, the aspect of A1) is preferable.

When one or both of the cyclic halosilane and the reducing agent are added dropwise in the manners A1) to C1) above, the concentration of the cyclic halosilane solution or dispersion is preferably 0.01 mol / L or more, more preferably 0.02 mol / L. It is L or more, more preferably 0.04 mol / L or more, and particularly preferably 0.05 mol / L or more. If the concentration of cyclic halosilane is too low, the amount of solvent that must be distilled off when isolating the desired product increases, which tends to reduce productivity. On the other hand, the upper limit of the concentration of the cyclic halosilane solution or dispersion is preferably 1 mol / L or less, more preferably 0.8 mol / L or less, still more preferably 0.5 mol / L or less.

The lower limit of the temperature at the time of dropping (specifically, the temperature of the solution or dispersion for dropping) is preferably −198 ° C. or higher, more preferably −160 ° C. or higher, still more preferably −100 ° C. or higher. The upper limit of the temperature at the time of dropping is preferably + 150 ° C. or lower, more preferably + 100 ° C. or lower, still more preferably + 80 ° C. or lower, and particularly preferably + 40 ° C. or lower. The temperature of the reaction vessel (reaction temperature) may be appropriately set according to the type of cyclic halosilane or reducing agent, and the lower limit is usually preferably −198 ° C. or higher, more preferably −160 ° C. or higher. More preferably, it is −100 ° C. or higher. The upper limit of the temperature of the reaction vessel (reaction solution) is preferably + 150 ° C. or lower, more preferably + 100 ° C. or lower, still more preferably + 80 ° C. or lower, and particularly preferably + 40 ° C. or lower. When the reaction temperature is low, decomposition and polymerization of intermediate products and target products can be suppressed, so that the yield is improved. The reaction time may be appropriately determined depending on the degree of progress of the reaction, and is usually 10 minutes or more and 72 hours or less, preferably 1 hour or more and 48 hours or less, and more preferably 2 hours or more and 24 hours or less.

As an example, a scheme example using trichlorosilane as the halosilane, triphenylphosphine (PPh ₃ ) as the compound I, and N, N-diisopropylethylamine (DIPEA) as the tertiary amine in the above method (B) is shown below.

When trichlorosilane is used as a starting material and the above compound I is triphenylphosphine (PPh ₃ ), a complex containing a 6-membered ring dodecachlorocyclohexasilane (dodecachlorocyclohexasilane and triphenylphosphine) is usually used as in the above scheme. Is a coordinated neutral complex ([PPh ₃ ] ₂ [Si ₆ Cl ₁₂ ])). Since this cyclic halosilane neutral complex contains no silicon atom other than the silicon atom forming the ring structure, silane gas or organic monosilane is not generated during reduction, alkylation or arylation, or even if it is generated, its amount is low. It can be suppressed.

The yield and yield of the cyclic halosilane neutral complex generated in this cyclization reaction can be calculated by using the methylation reaction represented by the following scheme in which the complex reacts quantitatively.

The method for reducing the above cyclic halosilane neutral complex (for example, [PPh ₃ ] ₂ [Si ₆ Cl ₁₂ ]) to obtain cyclohexasilane is, for example, when LiAlH ₄ is used as the reducing agent, the following scheme is used. expressed.

The reduction reaction is usually preferably carried out in an atmosphere of an inert gas such as nitrogen gas or argon gas.

For the cyclic hydrogenated silane containing cyclohexasilane produced in the reduction reaction, for example, a solid (impurities such as by-produced salts) was solid-liquid separated from the reaction solution obtained after the reduction, and then the solvent was distilled under reduced pressure. After that, it is isolated by distilling cyclic hydrides or the like.

The above-mentioned solid-liquid separation method can be preferably adopted because of its simple filtration, but is not limited to this, and for example, a known solid-liquid separation method such as centrifugation or decantation can be appropriately adopted.

That is, it is preferable to include a step of performing solid-liquid separation at least twice after reducing the cyclic halosilane. For example, after the liquid containing cyclic hydride and the solid are once solid-liquid separated (first separation), the liquid containing cyclic hydride is preferably concentrated and a hydrocarbon solvent (hexane or the like) is used as a diluting solvent. After the addition, preferably the concentrated and precipitated solid may be separated again (second separation), and the operation from the first separation to the second separation may be repeated as necessary. After the first separation, solvent dilution, concentration, and solid-liquid separation are more preferably performed once or more, and may be repeated a plurality of times.
The solid-liquid separation may be performed twice or three times or more. The number of times of the solid-liquid separation is not particularly limited, but in consideration of productivity, the upper limit is about 5 times or less.

Next, the solution containing the cyclic hydride obtained by the solid-liquid separation is concentrated as necessary, and then the concentrated cyclic hydride (preferably cyclohexasilane) is distilled. This distillation is preferably vacuum distillation. The method of distillation under reduced pressure is not particularly limited, and the distillation may be carried out using a known distillation column.

For example, a solution containing cyclic hydride is distilled under reduced pressure to recover a fraction having an appropriate content of cyclic hydride (particularly cyclohexasilane) (first distillation), and then the recovered fraction is distilled again under reduced pressure. Therefore, a fraction having an appropriate content of cyclic hydride (particularly cyclohexasilane) may be recovered (second distillation), and if necessary, the second distillation may be repeated.
Distilling the cyclic hydrogenated silane reduces the aluminum content to the ppb order, and multiple distillations will further reduce the aluminum content.

The hydrogenated silane such as the cyclic hydrogenated silane thus obtained is preferably used as the hydrogenated silane of the present invention.
The polysilane composition of the present invention is obtained by mixing silane hydride and halosilane (preferably cyclic halosilane) before reducing silane hydride. In other words, the hydrogenated silane may be a reaction product of a halosilane for preparing a hydride and a reducing agent (preferably a hydrogenated silane distilled and purified after the reduction reaction), and the halosilane may be an external halosilane. preferable.
Here, the external halosilane is not the unreacted halosilane contained in the reaction product between the hydrogenated silane preparation halosilane and the reducing agent, but the reaction product between the hydrogenated silane preparation halosilane and the reducing agent. It refers to halosilane added from the outside to a certain hydrogenated silane.
The halosilane for preparing hydrogenated silane and the halosilane for external addition may have the same structure or may be different, but are preferably the same. One or more types of halosilane for preparing hydrogenated silane and halosilane for external addition may be used.
The mixture of halosilane and hydrogenated silane is preferably a solution and may contain a solvent as described above.

In order to perform doping as necessary, it is preferable to further include a step of mixing and / or contacting a compound having at least one element selected from Group 13 and Group 15.
The elements of Groups 13 and 15 and the compounds having the elements (nucleophiles) are as described above.

Mixing and / or contact is preferably carried out in the presence of an inert gas such as nitrogen gas or argon gas.
The mixing and / or contact temperature may be, for example, −40 to 60 ° C., preferably about 0 to 40 ° C.
The mixing and / or contact time may be, for example, about 1 to 72 hours and 5 to 36 hours.
Further, when mixing and / or contacting, it is preferable to carry out under light-shielding conditions.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited by the following examples as well as the present invention, and appropriate modifications are made to the extent that it can meet the purposes of the preceding and the following. Of course, it is possible to carry out, and all of them are included in the technical scope of the present invention.

<Manufacturing example 1>
Production of halosilane (dodecachlorocyclohexasilane (Si ₆ Cl ₁₂ )) A mixture containing [Ph ₄ P ⁺ ] ₂ [Si ₆ Cl ₁₄ ^2- ] in a 200 ml two-necked flask equipped with a stirrer under a nitrogen atmosphere. 0 g and 1.3 g of powdered aluminum chloride AlCl ₃ were added, and 84 g of benzene was added thereto. After stirring and reacting under room temperature conditions for 1 hour, benzene was distilled off under reduced pressure. 67 g of n-hexane was added to the obtained white solid, the mixture was stirred for 1 hour, allowed to stand overnight, and then filtered. From 77 g of the colorless and transparent filtrate obtained by filtration, 2.0 g of a white solid was obtained by distilling off hexane under reduced pressure. ²⁹ When Si NMR was measured, it was confirmed that Si ₆ Cl ₁₂ was generated.

<Manufacturing example 2>
Preparation of silane hydride A. Manufacture of cyclic halosilane ([Ph ₃ P] ₂ [Si ₆ Cl ₁₂ ]) After replacing the inside of a 3L four-necked flask equipped with a thermometer, condenser, dropping funnel and stirrer with nitrogen gas, the inside of the flask was put into the flask. 155 g (0.591 mol) of triphenylphosphine as a coordination compound, 458 g (3.54 mol) of diisopropylethylamine as a basic compound, and 1789 g of 1,2-dichloroethane as a solvent were added. Subsequently, 481 g (3.54 mol) of trichlorosilane as a halosilane compound was slowly added dropwise from the dropping funnel under 25 ° C. conditions while stirring the solution in the flask.

After completion of the dropping, the mixture was stirred as it was for 2 hours, and then heated and stirred at 60 ° C. for 8 hours to carry out a cyclization coupling reaction to obtain a uniform reaction solution. The obtained reaction solution was concentrated, 7200 g of chloroform was added, and the mixture was stirred and washed at room temperature for 1 hour, filtered, and the filtered residue was dried under reduced pressure to obtain a white solid (crude product).

Subsequently, 5 times the amount (mass basis) of dehydrated hexane was added to the white solid obtained above, and the mixture was stirred and washed at room temperature for 24 hours, and then filtered. The obtained filtration residue was washed and filtered again with hexane according to the same procedure as above, and the obtained filtration residue was dried under reduced pressure to obtain a cyclic halosilane compound (bis (triphenylphosphine) dodecachlorocyclohexaci). A refined product of orchid ([Ph ₃ P] ₂ [Si ₆ Cl ₁₂ ])) was obtained. All steps from washing to drying were performed in a nitrogen atmosphere. When the obtained refined product was measured by gas chromatography, the purified product contained 1% by mass of chloroform and 1% by mass of an amine salt (amine hydrochloride) as a halogenated hydrocarbon compound.

B. Production of Cyclohexasilane (Si ₆ H ₁₂ ) In a 10 L flask under a nitrogen atmosphere, Production Example 2 A. 1099 g of the purified product of cyclic halosilane obtained in 1 and 5226 g of diethyl ether were added, and the mixture was stirred at −40 ° C. To this, 2005 g of a 1M diethyl ether solution of LiAlH ₄ was added dropwise from the dropping funnel. After completion of the dropping, the mixture was stirred at −40 ° C. for 3 hours to carry out a reduction reaction. Then, after raising the temperature of the reaction solution to room temperature, solid-liquid separation (decantation) was performed under a nitrogen atmosphere, the diethyl ether solvent was distilled off from 6974 g of the obtained solution under reduced pressure, and then 3810 g of dehydrated hexane was added. Then, diethyl ether and hexane were distilled off again under reduced pressure to concentrate, and then solid-liquid separation (filtration) was performed to remove the precipitated solid. After further distilling off the solvent from the obtained filtrate and expelling it, the mixture was filtered to obtain 160 g of a crude cyclohexasilane product as a filtrate.

By distilling 139 g of the obtained crude cyclohexasilane product under reduced pressure (conditions: internal liquid temperature 41 to 53 ° C., pressure 120 to 200 Pa), 51 g of the crude cyclohexasilane product was obtained (GC purity (area%): 95.4% -98.1%). Next, 114 g of the obtained crude cyclohexasilane product was distilled again under reduced pressure (conditions: internal liquid temperature 35 to 43 ° C., pressure 60 to 97 Pa) to obtain 106 g of the main distilled cyclohexasilane product (GC purity (area). %): 98.0% to 99.1%).
<Chromatography (GC) conditions>
Detection: FID
Column: Capillary column with poly (5% diphenyl / 95% dimethyl) siloxane phase, 0.25 μm x 0.25 mm x 30 m
Vaporization chamber temperature: 250 ° C
Detector temperature: 280 ° C
Temperature rise conditions: 1) Hold at 50 ° C for 5 minutes, 2) Heat up to 250 ° C at a temperature rise rate of 20 ° C / min, 3) Raise to 280 ° C at a temperature rise rate of 10 ° C / min, 4) 10 at 280 ° C. Hold minutes

<Example 1>
Production of Polysilane Composition Under a nitrogen atmosphere, 265 mg (0.45 mmol) of dodecachlorocyclohexasilane (Si ₆ Cl ₁₂ ) obtained in Production Example 1 was placed in a 50 mL eggplant-shaped flask, and then 17.6 g of benzene was added. Dissolved. To the obtained solution, 81 mg (0.45 mmol) of the cyclohexasilane present distilled product (Si 6H ₁₂ ) obtained in Production Example ₂ was added, and the mixture was stirred under 25 ° C. conditions for 24 hours to obtain a colorless transparent solution. A polysilane composition having a molar ratio of Si ₆ Cl ₁₂ to Si ₆ H ₁₂ of 1: 1 was obtained (the aluminum content was about 1000 ppb in the polysilane composition).

Claims (13)

Halosilane (m = 3 to 8, X represents a halogen element) represented by the general formula Silicon X _{2 m and} hydrogenated silane (n = 3 to 8) represented by the general formula Si _n H _2n . A polysilane composition comprising, characterized in that the aluminum content is 0.01 ppb to 1000 ppm on a mass basis. The polysilane composition according to claim 1 , wherein the content (based on mass) of the halosilane is 0.01 to 10 mol with respect to 1 mol of the hydrogenated silane. Instead of the halosilane represented by the general formula Silicon X _2m ( _m = 3 to 8, X represents a halogen element), at least a part of the halogen element contained in the halosilane is from Group 13 and Group 15. The polysilane composition according to claim 1 or 2 , which comprises a compound substituted with at least one selected hetero element . The polysilane composition according to any one of claims 1 to 3 , wherein the halosilane is a cyclic halosilane represented by the general formula Silicon X _{2 m} (m = 5 to 6, X represents a halogen element). The polysilane composition according to claim 4 , wherein the cyclic halosilane is cyclic chlorosilane. The polysilane composition according to claim 5 , wherein the cyclic chlorosilane is dodecachlorocyclohexasilane. The polysilane composition according to any one of claims 1 to 6 , wherein the hydrogenated silane is a cyclic hydride (n = 5 to 6) represented by the general formula Si _n H _2n . The polysilane composition according to claim 7 , wherein the cyclic hydrogenated silane is cyclohexasilane. Halosilane (m = 3 to 8, X represents a halogen element) represented by the general formula Silicon X _{2 m ,} and hydrogenated silane (n = 3 to 8) represented by the general formula Si _n H _2n . To prepare a first polysilane composition having an aluminum content of 0.01 ppb to 1000 ppm on a mass basis.
Next, a hetero element was introduced in which at least a part of the halogen element of halosilane in the first polysilane composition was replaced with at least one hetero element selected from groups 13 and 15 using a nucleophilic reagent. A method for producing a polysilane composition of . The production method according to claim 9 , wherein the mixture of the halosilane and the hydrogenated silane is a solution. Claimed that the reaction using the nucleophile comprises a step of mixing and / or contacting the nucleophile having at least one hetero element selected from Group 13 and Group 15 with the first polysilane composition. The manufacturing method according to 9 or 10 . The hydrogenated silane is a reaction product of a halosilane for preparing hydrogenated silane and a reducing agent.
The production method according to any one of claims 9 to 11, wherein the halosilane is an external halosilane. The production method according to any one of claims 9 to 12, wherein the purity of the hydrogenated silane is 90% by mass or more.